/*  Copyright (c) 2003 PureSilk.Org  */
/* ====================================================================
 * 
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:  
 *       "This product includes software developed by the 
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written 
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */ 


/*
 * ActionFactory.java
 *
 * Created on July 26, 2002, 11:11 AM
 */

package org.puresilk.web.actions;

import javax.servlet.http.HttpServletRequest;
import java.net.*;
import org.puresilk.web.*;

/**
 * Factory class for building 
 * web actions for servlets.
 *
 * @author  dcon5052
 */
public class ActionFactory {
  	private ClassLoader loader = null;
  	 
  	 /** 
  	  * Load actions from default classpath
  	  */
  	public ActionFactory() {}
  	
  	/** 
  	 * Create an ActionFactory to load actions from 
  	 *  a specific directory.
  	 */
	public ActionFactory (String classdir)  throws Exception {
			loader = new URLClassLoader(new URL[] { 
							new URL(classdir)
			 } );
	}
    
    /** 
     * Factory method for creating actions.  Action type
     * is extracted from req parameters and used to create
     * the action class by name.  The action class is then
     * initialized using the request.  This version prepends
     * the <i>packageName</i> to the value in the action 
     * parameter in <i>req</i>.
     * 
     * @param req Servlet Request with embedded action parameter
     * @param packageName overrides the default package
     * 
     * @return initialized Action object or null if there was an error.
     */
    @SuppressWarnings("rawtypes")
    public WebAction createAction ( HttpServletRequest req, String packageName ) {
        String actType = req.getParameter("action");
        String className = packageName.trim() + "." + actType.trim();
        WebAction action = null;

		// if no custom classloader has been created use default
		// reflection methods....
		if ( loader == null)
	        try {
	            // create class from name and initialize it
				Class t =  Class.forName(className);
	            action = (WebAction)t.newInstance();
	    
	    		req.setAttribute("AFResult" ,"OK");
	        }
	        catch (Exception ex) { 
	            // invalidate action
	            action = null; 
	
				req.setAttribute("AFException", ex);
	        }
	    // if we have a custom classloader, use it    
        else
        	try {
        			Class c = loader.loadClass(className);
        			action = (WebAction)c.newInstance();
        	}
        	catch(Exception ex) {
				req.setAttribute("AFException", ex);
        	}
        
        // return results	
        return action;
    }

    /** 
     * Factory method for creating actions.  Action type
     * is extracted from req parameters and used to create
     * the action class by name.  The action class is then
     * initialized using the request. This version expects 
     * a fully qualified class name in the 'action' parameter
     * of <i>req</i>.
     *
     *  @param req servlet request object
     */
    public Action createAction ( HttpServletRequest req ) {
        return createAction ( req, "" );
    }
     
}
